Transmission fluid

My car is a 2003 Toyota Camry with 109,000 miles. At my most recent oil change the mechanic said the transmission fluid was extremely dark. He said if there had been no previous fluid change before 100,000 miles it would do more harm than good to change it now. I cannot find any record of this having been done. Is this advice correct? What does this mean for the function of the transmission?

I Would Say That A Transmission Flush Service Should Not Be Done In These Circumstances. However, A Service Whereby The Transmission Fluid Is Drained, The Filter Renewed, And The Fluid Refilled, Would Be A Good Idea.

Some places make a lot of money selling flushes. Some of these places don’t want to drain and refill. Find somebody who will do it correctly.

Whatever you do, use the EXACT transmission fluid specified for your vehicle. Accept no substitute. I’d even go so far as to buy Toyota brand fluid.


100% agree with CSA. Buy the fluid and pan gasket from Toyota. You mechanic can drain the fluid, drop the pan and clean it out, flush out the screen (filter) and put it back together. I think you need 4.1 qts of Toyota ATF so you will need to buy 5 qts at around $8/qt and $15 for the gasket. Then expect to pay about an hour labor to your mechanic.

Kudos to your mechanic for detecting this, but there is no harm in a fluid change described above. It might also be a good idea to buy about 8 qts of ATF and then go back about a month later and have a simple drain and refill (3.5 qts) if you are planning a long term relationship with this car. After that get the transmission serviced every 30k miles with a drop the pan and clean the screen every other service.

Just to let your mechanic know, the issues he has heard about come from having the transmission flushed (flush machine) without dropping the pan and cleaning the screen and then using universal ATF with some additives. That would be bad for your transmission.

@CSA and @Keith Right on! Flushing would distribute all the crud into areas where it would do a lot of harm. I would drain and change filter & clean the pan, and in view of the condition, do it again in about 15,000 to 20,000 miles. Then continue at 30,000 miles intervals.

Hmm, car is at 100k miles! Mechanics love this milestone. Time to do all kinds of service. But he prefers not to do anything to trans? Well your car is shifting fine. But fluid is dark. Darker than it should be. According to mechanics trained eye. Does your owner manual say service trans at 100k? Or never?

Flush - NO…drain and refill - YES. Toyota doesn’t recommend a Flush anyways. They recommend a drain and re-fill.

Thanks for all the good advice. My mechanic does not do this procedure so I have an appt. with a different mechanic for a drain and refill tomorrow. He seemed to know exactly what all of you recommended.

Good Deal. Thanks For Responding. Your Transmission Will Thank You, Too.